Snap button with pull-apart resisting structure

ABSTRACT

A snap button with pull-apart resisting structure includes a male and a female part. The male part is provided on a bottom surface with a raised portion, and a connecting head having a neck portion centered at and projected from the raised portion. A recess portion is provided on one side of the raised portion to create a difference in the distances from an end surface of the connecting head to the raised portion and to the recess portion. The female part includes a central through hole, a part of which is a non-full circular hole enclosed by an elastic frame and having a diameter slightly smaller than that of the connecting head on the male part, and the other part of the central through hole is an extended curved hole corresponding to the recess portion on the male part and enclosed by a raised frame of a predetermined height.

FIELD OF THE INVENTION

The present invention relates to a snap button, and more particularly to a snap button with pull-apart resisting structure that is not easily pulled apart and would maintain in a fastened state even if the snap button were subjected to an unexpected pull force.

BACKGROUND OF THE INVENTION

A snap button has been widely used on various kinds of garments and bags, and includes a male and a female part for connecting to two different parts of a garment or a bag to releasably fasten the two parts together.

FIG. 1 is a perspective view of a conventional snap button with the male and the female part 10, 20 thereof in a separated state. As shown, the male part 10 of the conventional snap button is provided on a bottom surface with a square raised portion 11 having an area slightly smaller than that of the male part 10. A connecting head 12 is centered at and projected from the raised portion 11. The connecting head 12 is formed at a root portion with a narrowed neck portion 13. The female part 20 is provided on a top surface with a square raised portion 21 having an area slightly smaller than that of the female part 20. A round hole is centered at the raised portion 21 on the female part 20. An elastic annular element 22 is supported in the round hole by a plurality of short compressible rods 23 radially extended from an outer wall surface of the elastic annular element 22 to an inner wall surface of the round hole, such that the elastic annular element 22 defines a central through hole 24 in the round hole on the female part 20 for the connecting head 12 on the male part 10 to insert thereinto.

When the male part 10 is fastened to the female part 20, a free end portion of the connecting head 12 first passes through the central through hole 24 defined by the elastic annular element 22 to forcibly push against the short compressible rods 23. When the free end portion of the connecting head 12 has passed through the elastic annular element 22, the elastic annular element 22 is engaged with the narrowed neck portion 13 of the connecting head 12 under a restoring force of the compressible rods 23 to thereby firmly hold the male part 10 to the female part 20.

In the above-structured conventional snap button, the connecting head 12 on the male part 10 has a size very close to that of the central through hole 24 on the female part 20. When the snap button in a fastened state is subjected to an unexpected pull force, the central through hole 24 defined by the elastic annular element 22 tends to easily expand, so that the male part 10 is easily separated from the female part 20 to undesirably release the snap button and accordingly the garment or the bag fastened using the snap button.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a snap button with pull-apart resisting structure, which is not easily pulled apart and would maintain in a fastened state even if the snap button were subjected to an unexpected pull force.

To achieve the above and other objects, the snap button with pull-apart resisting structure according to the present invention includes a male part and a female part. The male part is provided on a bottom surface within a predetermined area with a raised portion, and at a central area with a connecting head that projects from the raised portion and is formed at a root portion with a narrowed neck portion. An area of the bottom surface of the male part extended from an edge of the male part to a line in parallel with that edge and transversely passing through a center of the narrowed neck portion of the connecting head forming a recess portion in the raised portion, so that there is a difference between the heights from an end surface of the connecting head to the raised portion and to the recess portion. The female part is provided on a top surface with a raised portion that has an overall area slightly smaller than that of the female part, and at a central area with a through hole having predetermined size and shape. A part of the through hole is a non-full circular hole enclosed in an elastic frame and having a diameter slightly smaller than that of the connecting head on the male part. A groove is formed along an outer side of the elastic frame, and a plurality of spaced supporting rods being radially extended from an outer wall surface of the elastic frame to an inner wall surface of the groove. The other part of the through hole is located at a position corresponding to the recess portion on the male part and in the form of an extended and curved hole with a raised frame of a predetermined height extended along the extended curved hole.

In a preferred embodiment of the present invention, the raised frame on the female part has a height larger than that of the elastic frame to serve as a reinforcing element, and is movable in the recess portion.

In another operable embodiment of the present invention, the female part of the snap button is provided on a bottom surface at a position corresponding to the raised frame with a shallow curved recess portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein

FIG. 1 is a perspective view of a conventional snap button with male and female parts thereof in a separated state;

FIG. 2 is a perspective view of a snap button with pull-apart resisting structure according to the present invention with male and female parts thereof in a separated state;

FIG. 3 is a sectional view of the snap button of FIG. 2 with male and female parts thereof in a separated state;

FIG. 4 is a sectional view showing the male and female parts of the snap button of FIG. 3 in a fastened state; and

FIG. 5 is a sectional view of the fastened male and female parts of the snap button of FIG. 4 in a state of being subjected to an unexpected pull.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIG. 2 that is a perspective view of a snap button with pull-apart resisting structure according to an embodiment of the present invention. As shown, the snap button includes a male part 30 and a female part 40. The male part 30 is provided on a bottom surface with a substantially U-shaped raised portion 31 that has an area smaller than an overall area of the male part 30, and at a central area with a connecting head 32 projected from the raised portion 31. The connecting head 32 is formed at a root portion with a narrowed neck portion 33. An area of the bottom surface of the male part 30 enclosed in the U-shaped raised portion 31 is a recess portion 34 extended from an edge of the male part 30 to a line in parallel with that edge and transversely passing through a center of the narrowed neck portion 33 of the connecting head 32. Therefore, there is a difference between a height from an end surface of the connecting head 32 to the raised portion 31 and a height from the end surface of the connecting head 32 to the recess portion 34.

The female part 40 is provided on a top surface with a raised portion 41 that has an overall area slightly smaller than that of the female part 40, and at a central area with a through hole 44 having predetermined size and shape. A part of the central through hole 44 is a non-full circular hole having a diameter slightly smaller than that of the connecting head 32 on the male part 30 and enclosed in an elastic frame 42. A groove 47 is provided along an outer side of the elastic frame 42 with a plurality of spaced supporting rods 43 radially extended from an outer wall surface of the elastic frame 42 to an inner wall surface of the groove 47. The other part of the central through hole 44 is located at a position corresponding to the recess portion 34 of the male part 30 and in the form of an extended and curved hole 45. A raised frame 46 of a predetermined height is provided to extend along the extended curved hole 45. In a preferred embodiment of the present invention, the raised frame 46 has a height larger than that of the elastic frame 42, and is movable in the recess portion 34 on the male part 30.

Please refer to FIGS. 3 to 5 that are sectional views showing the male and the female part 30, 40 of the snap button of the present invention in separated, fastened, and forcibly pulled states, respectively. When an external force A is applied on the male part 30 of the snap button to fasten the male part 30 to the male part 40, as shown in FIGS. 3 and 4, the connecting head 32 an the male part 30 first passes through the central through hole 44 to press against the elastic frame 42, so that the elastic frame 42 is slightly elastically and radially push outward. When the external force A is continuously applied, and the narrowed neck portion 33 of the connecting head 32 on the male part 30 reaches at the central through hole 44, the previously elastically pushed elastic frame 42 is brought by a restoring force thereof to engage with the narrowed neck portion 33 and thereby firmly hold the male part 30 to the female part 40 to fasten the snap button in a normal manner, as shown in FIG. 4.

When the snap button in a fastened state is subjected to an unexpected pull force B, as shown in FIG. 5, the narrowed neck portion 33 of the male part 30 is brought by the pull force B to slide from the non-full-circular part of the central through hole 44 to the extended and curved hole 45, which is integrally extended from and communicating with the non-full-circular part of the through hole 44. Since the extended and curved hole 45 has a diameter smaller that that of the connecting head 32 on the male part 30, it effectively retains the connected head 32, and accordingly, the male part 30 thereto, preventing the male part 30 from being pulled apart from the female part 40 by the unexpected pull force.

Since the unexpected pull force would normally bring the neck portion 33 on the male part 30 to collide with and accordingly wear down an inner wall surface of the extended and curved hole 45 on the female part 40, it is necessary to prevent this undesirable effect. To this end, the raised frame 46 extended along the extended and curved hole 45 provides an increased load area to protect the snap button.

A shallow curved recess portion 48 is provided on a bottom surface of the female part 40 at a position corresponding to the raised frame 46 on the top surface of the female part 40. The shallow curved recess portion 48 allows a lower part of the connecting head 32 of the male part 30 to slide therein without being stuck to the bottom of the female part 40, ensuring that the narrowed neck portion 33 of the male part 30 subjected to an unexpected pull force could fully move into the extended and curved hole 45 to contact with the raised frame 46.

When it is desired to release the previously fastened snap button, simply slide the connecting head 32 and the narrowed neck portion 33 thereof out of the extended and curved hole 45 into the central through hole 44, and the snap button can be released in a normal way.

With the above arrangements, the snap button of the present invention in a fastened state is effectively protected from being undesirably pulled apart by an unexpected external pull force applied on the male part, and is therefore more practical for use.

The present invention has been described with a preferred embodiment thereof and it is understood that many changes and modifications in the described embodiment can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims. 

1. A snap button with pull-apart resisting structure, comprising a male part and a female part; said male part being provided on a bottom surface within a predetermined area with a raised portion, and at a central area with a connecting head that projects from said raised portion and is formed at a root portion with a narrowed neck portion; an area of the bottom surface of said male part extended from an edge of said male part to a line in parallel with that edge and transversely passing through a center of said narrowed neck portion of said connecting head forming a recess portion in said raised portion, so that there is a difference between a height from an end surface of said connecting head to said raised portion and a height from the end surface of said connecting head to said recess portion; and said female part being provided on a top surface with a raised portion that has an overall area slightly smaller than that of said female part, and at a central area with a through hole having predetermined size and shape; a part of said through hole being a non-full circular hole having a diameter slightly smaller than that of said connecting head on said male part and being enclosed in an elastic frame, and a groove being provided along an outer side of said elastic frame with a plurality of spaced supporting rods radially extended from an outer wall surface of said elastic frame to an inner wall surface of said groove; the other part of said central through hole being located at a position corresponding to said recess portion on said male part and in the form of an extended and curved hole with a raised frame of a predetermined height extended along said extended curved hole.
 2. The snap button with pull-apart resisting structure as claimed in claim 1, wherein said raised frame on said female part has a height larger than that of said elastic frame, and is movable in said recess portion on said male part.
 3. The snap button with pull-apart resisting structure as claimed in claim 1, wherein said female part is provided on a bottom surface at a position corresponding to said raised frame with a shallow curved recess portion. 